From: Nadeem Ansari (nadeem.ansari574@gmail.com)
Date: Thu Feb 19 2009 - 08:16:43 ARST
Hi Rauhann,
I also done lots of exercise regarding load sharing by router and found that
CEF by default do per source/destination load balancing and process
switching do per packet load balancing
Mr. Doyle and You both are correct.
Hi Experts,
But I also faced one strange scenario where you have four paths to a
destination network and two path of them are configured with "no ip
route-cache" to enable process switching and remaining two are CEF enabled,
in this case what will happen CEF behavior will take over or process
switching behavior will take over, As per my observation CEF behavior will
take care of load balancing, Need your aopinions
Regards
Nadeem
On 2/17/09, ALL From_NJ <all.from.nj@gmail.com> wrote:
>
> Hello, hope all is well with you.
>
> The link to the IP switching section is:
>
> http://www.cisco.com/en/US/docs/ios/ipswitch/configuration/guide/12_4/isw_12_4_book.html
>
> There are some interesting options for these commands, cef in particular.
>
> IMO, you do not need to memorize any of this, the docs seem pretty clear
> for
> this and as long as you know where to find this info, should be a few easy
> points.
>
> This link will help, although it probably will not answer all your
> questions. It is pretty helpful though.
>
>
> http://www.cisco.com/en/US/products/sw/iosswrel/ps1828/products_tech_note09186a00801e1e46.shtml
>
> HTH,
>
> Andrew Lee Lissitz
>
>
>
>
> On Tue, Feb 17, 2009 at 5:31 AM, Ruhann <groupstudy@ru.co.za> wrote:
>
> > Hi
> >
> > Guys, please correct on the following
> >
> > In the event of load-sharing, ie one router with 2 link to another
> > By default routers running IOS 12.4 and later have CEF enabled by default
> > on
> > most interfaces.
> >
> > Default CEF will use per source/destination load-balancing,
> > CEF per packet can be enabled with "ip load-sharing per packet"
> >
> > Then, you have fast switching and process switching:
> > Fast Switching (enabled with no ip cef and ip route-cache) does per
> > destination load-balancing only
> > when Process Switching (enabled with no ip route-cache) does per-packet
> > load-balancing again.
> >
> > Please verify if above is correct, reason I asking, is I have found more
> > descrepencies with the DOC-CD,
> > claiming default cef does per dst only, but mr Doyle says it does per
> > src/dst.
> >
> > (I have come to trust the Mr Doyle's teaching over the Doc-Cd, even
> though
> > his articles any not only cisco related.)
> >
> > PS I did not mentioned here is the switching mechanism on the input
> > interface, as I am only after the differences conceptually.
> >
> > Regards
> > --
> > <ruhann>
> >
> >
> > Blogs and organic groups at http://www.ccie.net
> >
> > _______________________________________________________________________
> > Subscription information may be found at:
> > http://www.groupstudy.com/list/CCIELab.html
> >
> >
> >
> >
> >
> >
> >
> >
>
>
> --
> Andrew Lee Lissitz
> all.from.nj@gmail.com
>
>
> Blogs and organic groups at http://www.ccie.net
>
> _______________________________________________________________________
> Subscription information may be found at:
> http://www.groupstudy.com/list/CCIELab.html
Blogs and organic groups at http://www.ccie.net
This archive was generated by hypermail 2.1.4 : Sun Mar 01 2009 - 09:44:12 ARST